GLASS FIBER REINFORCED RESIN TANK WITH PARTICULAR JOINT STRUCTURE

CITERNE EN RESINE ARMEE DE FIBRES DE VERRE, ET SON JOINT D'ASSEMBLAGE PARTICULIER

English Abstract

3342-369
ABSTRACT
Two halves of a tank are secured together by an external lay-up
comprising corrosion-resistant resin. Each tank half includes an outer struc-
tural wall and an inner liner, the structural wall comprising corrodible
resin, the liner comprising corrosion-resistant resin, the structural wall
ending short of the inner end of the tank half, and the liner being radially
enlarged at the inner end of the tank half to cover the inner end of the
structural wall.
S21104A-

Claims

3342-369

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A fiber reinforced resin tank comprising a pair of generally cylin-
drical tank halves each closed at an outer end and open at an inner end and
including an outer structural wall and an inner liner, the structural wall com-
prising corrodible resin, the liner comprising corrosion-resistant resin, the
structural wall ending short of the inner end of the tank half, the liner
being radially enlarged at the inner end of the tank half to cover the inner
end of the structural wall, and the tank halves being secured together by an
exterior lay-up comprising corrosion-resistant resin.
2. A tank as claimed in claim 1 wherein the resin of the exterior lay-
up is the same kind of resin as the liner resin.
3. A tank as claimed in claim 1 including an additional lay-up over
said exterior lay-up, the additional lay-up comprising corrodible resin.
4. A tank as claimed in claim 1 wherein the reinforcing fibers are
glass fibers.
4-

S21104A-

Description

33~2 369

This invention relates generally to glass fiber reinEorced resin
storage tanks, and more particularly to the joint structure between two halves.
Glass fiber reinEorced resin tanks are typically made oE isophthalic
resin, chopped glass strands, and a filler such as sand. External ribs of
woven glass roving and glass filament windings impregnated with resin are
usually provided. Generally a resin-rich liner is also provided consisting of
about a 20-mil thickness of resin with a surface mat and an 80-mil thickness
of resin and chopped glass strands. When a tank is to be used ~o store cor-
rosive liquids which attack isophthalic resin, polyester or vinylester resin
may be used as the l:iner resin. The tanks are made of two halves, as generally
disclosed in United States Patent ~o. 3,700,512, joined by an external lay-up
oE a plurality of interleaved layers of woven glass roving and chopped strands
mat impregnated with resin. Prior to my invention, tanks for corrosive liquid
service were also provided at the joint with an internal lay-up of a plurality
of interleaved layers of woven glass roving and chopped strand mat impregnated
with a corrosion-resistant resin such as polyester or vinylester resin. For
appl:ication oE this internal lay-up, onc of the tank halves had to be provided
with a manway, which aclded considerably to the cost of the tank.
SUMMARY OF '1'~l~. [NV~NTION
[n accordance w:i.th the :invent:ion, a jOillt structure iS provided,
in a tank for corrosive liquid servi.co, whe:re:in no internal lay-up is requirecl,
and there~ore no m.lnway is requi:red, but the isopht}lalic resin portion oE the
tank is nevertheles.s sh:ielded :Erom corros:ive llquids.
More specifically, the invention provicles a fiber reinforced resin
tank comprising a pair oE generally cylindrical tank halves each closed at an
outer end and open at an inner end and including an outer structural wall and

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S2110~A- - 1 - ~
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an inner liner, the structural wall comprising corrodible resin, the liner
comprising corrosion-resistant resin, the structural wall ending short of the
inner end of the tank half, the liner being radially enlarged at the inner
end of the tank half to cover the inner end of the structural wall, and the
tank halves being secured together by an exterior lay-up comprising corrosion-
resistant resin.
The invention is more fully described hereinafter, reference being
had to the accompanying drawings wherein:
Figure l is a side view of two tank halves constructed in accordance
with the invention and disposed in relative positions suitable for the
application of an external lay-up to complete a tank;
Flgure 2 is a fragmentary sectional view taken generally along line
2-2 of Figure l, but including an external lay-up joining the two tank halves;
and
Figure 3 is a view similar to Flgure 2 but illustrating a tank of
the prior art.
With respect to the drawings, Figure 1 shows two generally cyli.n-
drical tank halves 10 constructed in accordance with the invention and having
open inner ends and closed outer ends. The tank halves 10 are shown as
generally cylindrical 'but having tapered sidowalls, as made on L tLpered man-
clrel such as disc:Losed in l)nited States Patent No. 3,700,512, but the sicLewalls
may be truly cyl:ind:rical :i:E tho tank l,alves 10 are made on a co:llaps:ible
manclrel, such as cllsclosecl in Un:ited States Patent No. ~,233,020. 'I'he normal
external ribs on tlle tank halves 10 are omittecl.
As shown in Figure 2, each tank hal:E 10 inclucles L liner lOa and a
structural wall lO'b, thc usual surface mat and chopped glass strands being
omitted in the representation o:E the liner lOa and the usual chopped glass


-- 2 --

~2~5~3~

resin in the structural wall 20b are corrodible.
In each case, it will be seen that corrosive liquids in the tank
would have no contact with the resin of the structural wall lOb or 20b or the
resin of the lay-up lOd or 20d, but the prior art construction requires the
interior lay-up 20c and *herefore also requires a manway in one of the tank
halves 20.
Various modifications may be made in the structure shown in Figures
1 and 2 and described above, without departing from the scope of the invention.